Isabellenhütte wins case against TT electronics GmbH

Editor: Staff Editor

The Supreme Court’s ruling is effective immediately. Given that shunts of the type in question may now not be produced in or imported to Germany without the consent of Isabellenhütte, it is expected that the judgements of both the Supreme Court and the higher regional court in Karlsruhe will have a far-reaching impact.

In December 2010, Germany's Federal Supreme Court found in favour of Dillenburg based Isabellenhütte Heusler GmbH & Co. KG in its legal dispute with TT electronics GmbH from Freising, near Munich and part of the TT company. Legal proceedings started in 2005 and were heard by several different courts before reaching the country's Supreme Court.
In 2009, Karlsruhe's higher regional court found in favour of Isabellenhütte in its long-running patent infringement dispute with TT electronics GmbH, ruling that the current sensing resistors models CSS and OARS-1 marketed by TT electronics infringed Isabellenhütte's patent in Germany. The court ruled that Isabellenhütte was therefore entitled to damages and access to data, and it was also entitled to force TT electronics to suspend its activities in question.
Parallel to this patent infringement case, TT electronics GmbH attempted to use a patent nullity action to undermine the validity of Isabellenhütte's patent in Germany and thereby remove the legal basis for Isabellenhütte's patent infringement case. However, the country's Supreme Court has judged that Isabellenhütte's patent in Germany for current sensing resistors on the milliohm scale is valid (File No. X ZR 121/08).
Import ban
The Supreme Court’s ruling is effective immediately. Given that shunts of the type in question may now not be produced in or imported to Germany without the consent of Isabellenhütte, it is expected that the judgements of both the Supreme Court and the higher regional court in Karlsruhe will have a far-reaching impact.
The shunts in question are current sensing resistors for milliohm values, made using electron beam welding. At Isabellenhütte, these resistors are known as ISA-WELD products, comprising typical product groups such as BVS, BVR, BVB, BVT, BRS. The resistors are sold to numerous industries: the main sales targets are automotive electronics, for instance as a component used in battery management and the energy sector.
Their structure and the special methods used in their manufacturing mean that these components are ideal for high current measurement even when space is extremely restricted. This is the reason for the long-running success of Isabellenhütte's product portfolio.